Idle problem plz help

[Byrdman]

Hi everybody I'm new to the forum and need a little help so right to the problem i have an 07 gz250 I can go outside choke off and start the bike and it will idle perfect for as long as I don't touch the throttle but the minute I rev up the bike it will stay in a high idle as soon as I adjust the idle back down to normal the bike dies the throttle response is a lil sluggish compared to my brothers Honda rebel 250 with this being said I have cleaned carb I mean really cleaned it with carb cleaner 6 times not even joking I also took off intake boot and checked no cracks or nothing rubbers like new I replaced o ring between intake boot and cylinder head also checked diaphragm looked new no tears or nothing as well as peacock vacuum line tested petcock function works as it should fresh gas the bike has 6k miles on it was owned by an older guy and stored in garage it's entire life which probably explains why the rubber looks new but anyways any ideas?